Bone exhibits positive form birefringence dominated by and dependent upon the orientation of its collagen. The biomechanical efficacy of bone as a tissue is largely determined by collagen fibers of preferred orientation and distribution (and corresponding orientation of mineral crystallites), and evidence is accumulating to demonstrate that this efficacy extends to function at the organ level. ...

This study used density functional theory and the quantum transport method to investigate interfacial coupling spin of transition metals (TMs) with a Fe, Co, Ni/2H-VSe2 hybrid nanostructure. Because indirect TM-Se-V led an obvious reduction magnetic moment disappearance half-metal characteristics 2H-VSe2, expected spin-filtering effect individual TMs 2H-VSe2 deteriorated at contact region. Neve...

A ruthenium-catalyzed intermolecular [3 + 2] cycloaddition of 2H-azirines and activated alkynes is reported, which provides polysubstituted pyrroles in moderate to good yields. This approach features a C-N bond cleavage of 2H-azirines by a ruthenium catalyst. The results of this study would provide a complementary method to synthesize polysubstituted pyrroles from the known 2H-azirine approache...

The main structural unit of the title compoud, C(21)H(18)O(6), is a fused three-ring group consisting of coumarin and tetra-hydro-pyrane ring systems. Two C atoms of the tetra-hydro-pyran ring are displaced by 0.295 (3) and -0.360 (2) Å from the mean plane of coumarin ring. The dihedral angle between the phenyl and coumarin rings is 73.94 (3)°. Inter-molecular O-H⋯O hydrogen bonds are present i...

In this paper, we describe our synthesis of four key building blocks for the total synthesis of psymberin (1) and its C4 epimer (2). Despite early difficulties in processing material to the advanced intermediate stage, we have been successful in developing high-yielding syntheses for the pyran core, natural side chain, 4-epi side chain, and aryl fragments of the molecule. Our findings from the ...

The asymmetric unit of the title compound, C(19)H(20)N(2)O(3), contains two independent mol-ecules in both of which the pyrrolidine ring adopts an envelope conformation, but with a C atom as the flap in one mol-ecule and the N atom in the other. The pyran ring adopts a half-chair conformation in both mol-ecules. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds and C-H⋯π inter-acti...

(a) Define a linear mapping R2h h : R 5 → R3 according to the full weighting scheme (see Lecture slides). Setup the respective matrix R2h h . (b) Define a linear mapping Ph 2h : R 3 → R5 which prolongates a solution vector from the coarse to the fine grid using linear interpolation (see Lecture slides). Setup the respective matrix Ph 2h. (c) Based on the matrices R2h h , P h 2h and Ah, compute ...

With reference to the impending transition of chemical industry from depleting fossil raw materials to renewable feedstocks--the end of cheap oil is predicted for 2040 at the latest--this account gives an overview on chemically transforming carbohydrates, by far the major part of the annually regrowing biomass, into the following unsaturated O- and N-heterocycles with versatile industrial appli...

Abbreviations: Pyrazon, 5-amino-4-chloro-2-phenyl-3 (2H) pyridazinone; o-methyl-pyrazon, 5-amino-4-chloro-2(2-methylphenyl)-3(2H)-pyridazinone; m-methyl-pyrazon, 5-aminoj4-chloro-2(3-methylphenyl) 43 (2H) -pyridazinone; p-methyl-pyrazon, 5-amino-4-chloro-2(4-methylphenyl) -3 (2H) pyridazinone. Requests for reprints should be sent to Prof. Dr. F. Lingens, Institut für Mikrobiologie und Molekular...

A two-step sequence for the synthesis of various 3,4-dihydro-2H-1,3-thiazines is presented. In the first step, 2H-1,3-thiazines were prepared by a new multicomponent reaction (MCR). Starting from β-chlorovinyl aldehydes, this MCR offers an efficient and facile access to 2,2-dialkyl- and 2-alkyl-2-aralkyl-5,6-diaryl-2H-1,3-thiazines. The potential of these products in subsequent reactions was ve...